/*
 * Copyright 2004-2007 Gary Bentley 
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may 
 * not use this file except in compliance with the License. 
 * You may obtain a copy of the License at 
 *    http://www.apache.org/licenses/LICENSE-2.0 
 *
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 * See the License for the specific language governing permissions and 
 * limitations under the License.
 */
package org.sourceprojects.cappadocia.org.josql.internal;

import java.util.List;
import java.util.ArrayList;

import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;

import org.sourceprojects.cappadocia.com.gentlyweb.utils.FilterException;
import org.sourceprojects.cappadocia.com.gentlyweb.utils.GeneralFilter;

public class MethodFilter {

	private Class c = null;
	private List ps = null;
	private String name = null;
	private int type = -1;
	private List modifiers = null;

	public MethodFilter() {

	}

	public MethodFilter(Class c) {

		this.c = c;

	}

	public void setClass(Class c) {

		this.c = c;

	}

	public void addModifier(int m) {

		if (this.modifiers == null) {

			this.modifiers = new ArrayList();

		}

		this.modifiers.add(Integer.valueOf(m));

	}

	public List filter() throws IllegalAccessException,
			InvocationTargetException, FilterException {

		Method[] ms = this.c.getMethods();

		List res = new ArrayList();

		if (ms.length == 0) {

			return res;

		}

		GeneralFilter gf = null;

		if (this.name != null) {

			gf = new GeneralFilter(Method.class);
			gf.addField("name", name, this.type);

		}

		for (int i = 0; i < ms.length; i++) {

			Method m = ms[i];

			if (gf != null) {

				if (!gf.accept(m)) {

					continue;

				}

			}

			// Now check that it has the correct modifiers...
			if (!this.hasModifiers(m)) {

				continue;

			}

			// Now check the parm types.
			if (!this.hasParameters(m)) {

				continue;

			}

			res.add(m);

		}

		return res;

	}

	private boolean hasParameters(Method m) {

		if (this.ps == null) {

			return true;

		}

		// Allowing for widening of types here.
		Class[] mpt = m.getParameterTypes();

		if (mpt.length != this.ps.size()) {

			return false;

		}

		for (int i = 0; i < mpt.length; i++) {

			Class c = mpt[i];

			Class pc = (Class) this.ps.get(i);

			if (pc == null) {

				// Skip this one because we can't compare...
				continue;

			}

			if (!c.isAssignableFrom(pc)) {

				return false;

			}

		}

		return true;

	}

	private boolean hasModifiers(Method m) {

		if (this.modifiers != null) {

			int mmods = m.getModifiers();

			for (int i = 0; i < this.modifiers.size(); i++) {

				int in = ((Integer) this.modifiers.get(i)).intValue();

				if ((mmods & in) == 0) {

					return false;

				}

			}

		}

		return true;

	}

	public void setParameterTypes(List pt) {

		this.ps = pt;

	}

	public void setName(String n, int type) {

		this.name = n;
		this.type = type;

	}

}
